AI 中文总结
该研究提出热化包（冷却时称冰块）策略，定义完美与最优热化包，发现热制备中最优包非最冷包，存在类似姆佩姆巴效应的现象，在多种模型中演示该概念并扩展到有限读出时间优化。
AI 中文摘要
向平衡态的弛豫通常可通过改变环境或进一步冷却远离平衡态的系统来加速。本文提出一种独特策略：热化包，即预先制备的辅助系统，后续与目标系统耦合以加速其向指定热态的弛豫，因此热化包以制备工作量换取等待时间的减少。当目标为冷却时，我们将此类包俗称为冰块。与普通冷却剂不同，热化包的特征不仅包括其温度或热容，还包括其微观制备。我们根据耦合动力学中最慢弛豫模式的抑制能力定义完美包和最优包：完美包可完全消除该模式，而最优包可将其振幅最小化。我们证明，在一般条件下，完美包存在于接近平衡的热制备中。令人惊讶的是，对于渐近弛豫，热制备中的最优包通常并非最冷的包：将包冷却至慢模式抵消最优值以下会恢复非零慢模式，从而减缓弛豫，产生类似姆佩姆巴效应的包现象。我们在可精确求解的Metropolis动力学、最小二量子比特模型以及边界耦合的相互作用伊辛自旋系统中演示了该概念。我们还将框架扩展到针对有限读出时间优化的包。最后，我们证明完美包的轮廓可连接平凡的浴平衡点与非平凡的强姆佩姆巴或强逆姆佩姆巴点。
英文摘要
Relaxation toward equilibrium is usually accelerated by modifying the environment or by cooling a system further from equilibrium. Here we introduce a distinct strategy: thermalization packets, auxiliary systems prepared in advance and later coupled to a target system to accelerate its relaxation toward a prescribed thermal state. Thus, thermalization packets trade preparation effort for reduced waiting time. When the objective is cooling, we colloquially refer to such packets as ice cubes. Unlike ordinary coolants, thermalization packets are characterized not only by their temperature or heat capacity, but also by their microscopic preparation. We define perfect and optimal packets by their ability to suppress the slowest relaxation mode of the coupled dynamics: perfect packets eliminate it entirely, while optimal packets minimize its amplitude. We show that, under generic conditions, perfect packets exist among thermal preparations near equilibrium. Surprisingly, for asymptotic relaxation, the optimum among thermal preparations is generally not the coldest packet: cooling the packet beyond the slow-mode-cancelling optimum restores a nonzero slow mode and can therefore slow relaxation, yielding a packet analog of the Mpemba effect. We demonstrate the concept in exactly solvable Metropolis dynamics, a minimal two-qubit model, and a boundary-coupled interacting Ising-spin system. We also extend the framework to packets optimized for finite readout times. Finally, we show that the perfect-packet contour can connect the trivial bath-equilibrium point to a nontrivial strong Mpemba or strong inverse-Mpemba point.
